1. Field of the Invention
The present invention relates to a copying machine having a binding function capable of automatically binding discharged copied sheets using a predetermined holding member such as a staple or a clip.
2. Description of the Related Art
Copying machines having a binding function are proposed for instance as described in Japanese Patent Unexamined Publication No. 48777/1989.
Such a binding function in the copying machine contributes to reducing manpower and reducing the time required for copying work in offices and the like. The time savings is especially noticeable when utilized in combination with a discharged sheet sorting function and the like.
When binding the copied sheets by a binding function, there is a limit in the number of copies that can be bound. This maximum bindable number of copies is only indicated in an instruction manual and the like in a conventional copying machine with a binding function.
On the other hand, the number of copied sheets to be discharged from the copying machine depends on the combination of the number of sheets of an original and the selected copying mode. For example, in a double-sided copying mode in which each of plural single-sided original sheets is sequentially copied on both sides of a copying sheet, the number of copied sheets to be discharged is half that of the originals. In contrast, in a separate copying mode in which a sheet of a double-sided original is copied in two separate copying sheets, the number of copied sheets to be discharged is twice that of the original.
Since the number of copied sheets with respect to that of the sheets of an original vary depending on the copying mode in this way, there has existed a shortcoming that it is difficult to correctly know the maximum bindable number of sheets of an original prior to copying.